1. Field of the Invention
The present invention relates to phosphate reactive dry or wet-laid sheets and phosphate structures made therefore. Such structures are useful as packaging materials, packing structures, partitions, wall decorations sheets for the interior surface of buildings, aircraft, automobiles, and the like.
These compositions can also be bonded to other substrates such as paper, ceramic, metallic surfaces or the like for a particular use.
2. The Prior Art
A number of references can be found in the prior art which describe phosphate ceramic materials, laminated composites and processes for their preparation.
U.S. Pat. No. 4,569,878, for example, describes laminated composites prepared from the reaction of a metal oxide, calcium silicate and phosphoric acid. These composites are characterized in that they have superior fire resistant properties. The laminated structures described in this reference comprise contiguous layers of a selected structural layer material with intervening layers of the bonding composition used which comprised a metal oxide calcium silicate and the phosphoric acid.
The same reactants are also disclosed and applied in U.S. Pat. No. 4,375,516. This reference relates to the preparation of rigid, water resistant phosphate ceramic materials and processes for either foamed or non-foamed materials. Advantages are provided with the instant invention by using paper and board making technology to form phosphate reactive sheets.
The instant phosphate reactive paper-like materials are light and flexible and, if desired, can be torn or cut into a particular size. The light, flexible nature of these substrates allows the sheet to be bent, folded, or molded around particular objects or in a desired configuration. The application of phosphoric acid will then cause the reactive sheet to cure into a solid, rigid form.
Advantageously, by using either wet laying or dry laying techniques a reactive sheet product is prepared which contains an unusually large amount of dry material that can be wetted with a modest portion of reactant solution. Furthermore, the use of these techniques allows the preparation of a useful, reactive sheet composition which, moreover, is unusually compact and easily moved or stored until it is wetted with a reactive solution and allowed to react to give the solid product.